code: def test_gradcheck(self, device):
      points = torch.rand(
          1,
          8,
          2,
          device=device,
          dtype=torch.float64,
          requires_grad=True,
      )
      K = torch.rand(1, 3, 3, device=device, dtype=torch.float64)
      new_K = torch.rand(1, 3, 3, device=device, dtype=torch.float64)
      distCoeff = torch.rand(1, 4, device=device, dtype=torch.float64)
  
      assert gradcheck(
          distort_points,
          (points, K, distCoeff, new_K),
          raise_exception=True,
          fast_mode=True,
      )
  
file_path: kornia/test/geometry/calibration/test_distort.py
imports: import pytest
  import torch
  from torch.autograd import gradcheck
  from kornia.geometry.calibration.distort import distort_points
  from kornia.testing import assert_close
label_desc: Use image node_id 4 for calling the TestDistortPoints obj's underlying member method code with example usage: obj.test_gradcheck(device) without return types